A semiconductor memory device includes memory cells for storing information and switching elements for updating memory information. Reading of information stored in a semiconductor memory device is influenced by the initial storage state when writing and the state when reading and the like. For example, a dynamic random access memory (DRAM) stores a voltage value in a memory cell capacitor as memory information. There is leakage current in a memory cell capacitor or a transistor that serves as a switching element of a DRAM, and hence if the DRAM is unused for a long time period it will not be possible to read out the same information as the information at the time of writing. Therefore, in the case of a DRAM, information stored in memory cells is updated by periodic refresh operations. The amount of time for which information stored in a memory cell can be maintained depends on various factors. The power supply voltage value when writing the information is one such factor.
For example, a semiconductor memory device with a one-gigabit memory capacity has approximately one billion memory cells in a chip, and there are variations in the data retention characteristics of the respective memory cells. In general, in a semiconductor memory device, redundancy repair is performed in which memory cells that do not meet specification performance requirements are replaced with other memory cells that meet the specification performance requirements.
Patent Document 1 discusses technology that corresponds to the clock frequency dependence of a consumption current request in which a circuit that performs analog control of an output voltage by performing a voltage comparison with a reference voltage value, and a circuit that performs digital control of an output voltage in synchrony with a clock signal that acts as a trigger for a memory access command are mounted on a semiconductor memory device chip. Further, Patent Document 2 discusses technology that, with respect to a power supply for a data output circuit, supplies a high voltage that exceeds a power supply voltage.    [Patent Document 1] Japanese Laid-open Patent Publication No. 2009-268091    [Patent Document 2] Japanese Laid-open Patent Publication No. 6-204847
To appropriately perform redundancy repair for a semiconductor memory device, it is performed to detect memory cells that do not meet specification performance requirements with favorable reproducibility, and thus voltage values and the like can be accurately set in tests performed for that purpose.